Motion control

Abstract

Motion of rams in fluid cylinders to drive machine parts is equalized by equalization chambers between drive chambers for equalizing outward and inward driven motion of the rams and the attached machine parts, irrespective of portions of loads and forces on the machine parts in relation to the rams. Duplicated machine parts may be closely positioned or widely separated, while providing the same controlled equalized movement irrespective of loading. The movable elements may be tilted to new angular positions before they are translated by the rams.

I claim: 
     
       1. A system for controlling movement of machine parts, comprising:
 a fixed machine part; 
 a movable machine part; 
 first and second rams connected to the movable machine part; 
 first and second cylinders connected respectively to the first and second rams; 
 first and second opposed drive chambers in each of the cylinders; 
 third and fourth opposed equalizing chambers in each of the cylinders; 
 a fluid pressure source and a fluid receiver; 
 a three-position four-way valve; 
 fluid interconnections between the fluid pressure source and the three-position four-way valve and between the fluid receiver and the three-position four-way valve; 
 a first fluid conduit between the three-position valve and the first drive chambers; 
 a second fluid conduit between the second drive chambers and the three-position valve; 
 a third fluid conduit between the third chamber of the first cylinder and the fourth chamber of the second cylinder; and 
 a fourth fluid conduit between the fourth chamber of the first cylinder and the third chamber of the second cylinder for equalizing movement of the first and second rams, further comprising a second three-position four-way valve connected to the fluid pressure source and to the fluid receiver and the third and fourth fluid conduits for tilting opposite sides of the movable machine part upward and downward when the second three-position valve is in a first position or in a third position. 
 
     
     
       2. The system of  claim 1 , wherein the first and second opposed drive chambers are outer chambers in the cylinders, further comprising a pilot check valve connected in the first conduit adjacent the three-position four-way valve for allowing fluid to flow from the pilot check valve to the first chambers when the three-position valve is in a first position. 
     
     
       3. The system of  claim 2 , wherein the pilot check valve has a pilot line connected to the second fluid conduit near the three-position valve, wherein the three-position valve is in a third position, pressure from the pressure source opens the check valve to permit fluid to flow from the first conduit to the fluid receiver. 
     
     
       4. The system of  claim 1 , wherein in each of the cylinders the first chambers and third chambers are separated by a first movable piston, the second and fourth chambers are separated by a second movable piston, wherein the third and fourth chambers are separated by a divider fixed in each of the cylinders, and wherein the first and second pistons are connected to one of the rams and the one of the rams is movable through and is sealed for movement in the divider. 
     
     
       5. The system of  claim 1 , wherein the machine is a press, shear or press brake. 
     
     
       6. The system of  claim 1 , further comprising third and fourth pilot check valves connected in the third and fourth conduits near the second three-position valve. 
     
     
       7. A system for controlling movement of a movable plane in a machine having stationary and movable planes, comprising:
 a movable plane; 
 first, second, third and fourth cylinders; 
 first, second, third and fourth rams in the first, second, third and fourth cylinders connected to the movable plane remote from each other to move the movable plane between parallel positions and to selectively rotate the movable plane around crossed axes; 
 first and second opposed drive chambers in each of the cylinders; 
 third and fourth equalizing chambers in each of the cylinders; 
 a fluid pressure source and a fluid receiver; 
 first, second and third three-position four-way valves connected to the fluid pressure source and the fluid receiver; 
 first and second fluid conduits connected to the first three-position valve; 
 third and fourth fluid conduits connected to the second three-position valve; 
 fifth and sixth fluid conduits connected to the third three-position valve; 
 the first fluid conduit being connected to the first chambers in the first, second, third and fourth cylinders; 
 the second fluid conduit being connected to the second chambers in the first, second, third and fourth cylinders; 
 the third fluid conduit being connected between the third chamber in the first cylinder and the fourth chamber in the third cylinder; 
 the fourth fluid conduit being connected between the fourth chamber in the first cylinder and the third chamber in the third cylinder; 
 the fifth fluid conduit being connected between the third chamber in the second cylinder and the fourth chamber in the fourth cylinder; 
 the sixth fluid conduit being connected between the fourth chamber in the second cylinder and the third chamber in the fourth cylinder; 
 wherein placing the first three-position valve in a first position connects the fluid pressure source to the first conduit and to all of the first chambers, and connects the second conduit and all of the second chambers to the fluid reservoir, to provide movement of the movable plane in a first direction while fluid flows in the third, fourth, fifth and sixth conduits between the respective third and fourth chambers of the cylinders to equalize movement of the rams; 
 wherein placing the first three-position valve in a third position connects the fluid pressure source to the second conduit and to all of the second chambers, and connects the first conduit and all of the first chambers to the fluid reservoir, to provide movement of the movable plane in a second direction opposite to the first direction while fluid flows in the third, fourth, fifth and sixth conduits between the respective third and fourth chambers of the cylinders to equalize movement of the rams. 
 
     
     
       8. The system of  claim 7 , further comprising moving the second three-position valve to a first position for connecting the fluid pressure source to the third fluid conduit, and connecting the fourth fluid conduit to the fluid reservoir for tilting the movable plane clockwise about a first axis between connections of the second and fourth rams to the movable plane, and moving the second three-position valve to a third position connects the fluid pressure source to the fourth fluid conduit, and connects the third fluid conduit to the fluid reservoir for tilting the movable plane counterclockwise about the first axis between the connections of the second and fourth rams to the movable plane. 
     
     
       9. The system of  claim 7 , further comprising moving the third three-position valve to a first position for connecting the fluid pressure source to the fifth fluid conduit, and connecting the sixth fluid conduit to the fluid reservoir for tilting the movable plane clockwise about a second axis between connections of the first and third rams to the movable plane, and moving the third three-position valve to a third position for connecting the fluid pressure source to the sixth fluid conduit, and connecting the fifth fluid conduit to the fluid reservoir for tilting the movable plane counterclockwise about the second axis between the connections of the first and fourth rams to the movable plane. 
     
     
       10. The system of  claim 7 , wherein in each of the cylinders the first chambers and third chambers are separated by a first movable piston, the second and fourth chambers are separated by a second movable piston, wherein the third and fourth chambers in each cylinder are separated by a divider fixed in each cylinder, and wherein the first and second pistons in each cylinder are connected to one of the rams and the rams are movable through and sealed for movement in the dividers. 
     
     
       11. The system of  claim 7 , wherein the machine is a press and the movable plane is a platen. 
     
     
       12. A system for moving movable objects in parallel spaced positions by equalizing movement of rams with an ability to rotate the objects in shaping sheet metal for automobiles or in long twelve meter press brakes and moving objects in a machine having multiple movable objects, comprising:
 fixed first, second, third and fourth cylinders, 
 first, second, third and fourth rams mounted in the cylinders and connected to the movable objects, 
 first and second opposed drive chambers are in each of the cylinders, 
 four equalizing chambers in each of the cylinders, 
 first, second, third and fourth three-position four-way valves connected to a fluid pressure source and a fluid receiver tank, 
 first and second fluid conduits connected to the first three-position valve, 
 third and fourth fluid conduits connected to the second three-position valve, 
 fifth and sixth fluid conduits connected to the third three-position valve, 
 seventh and eighth fluid conduits connected to the fourth three-position valve, 
 the first fluid conduit being connected to the first chambers in the first, second, third and fourth cylinders, 
 the second fluid conduit being connected to second chambers in the first, second, third and fourth cylinders, 
 the third fluid conduit being connected between a third chamber in the first cylinder and a fourth chamber in the second cylinder, 
 the fourth fluid conduit being connected between a fourth chamber in the first cylinder and a third chamber in the second cylinder, 
 the fifth fluid conduit being connected between a third chamber in the third cylinder and the fourth chamber in the fourth cylinder, 
 the sixth fluid conduit being connected between a fourth chamber in the third cylinder  330  and a third chamber in the fourth cylinder, 
 the seventh fluid conduit being connected to sixth chambers in the first and second cylinders, and to the fifth chambers in the third and fourth cylinders, 
 the eighth fluid conduit being connected to fifth chambers in the first and second cylinders, and to sixth chambers in the third and fourth cylinders, 
 the second positions of the three-position valves being neutral with no connection to the chambers, 
 placing the first three-position valve in a first position connecting the fluid pressure source to the first conduit and to all of the first chambers and connecting the second conduit and all of the second chambers to the fluid reservoir to provide outward movement of the movable objects, fluid flowing in the third, fourth, fifth and sixth conduits between the respective third and fourth chambers of the cylinders and in the seventh and eighth conduits between respective fifth six sixth chambers to equalize movement of the rams, 
 placing the first three-position valve in a third position connecting the fluid pressure source to the second conduit and to all of the second chambers, connecting the first conduit  31  and all of the first chambers to the fluid reservoir, and providing inward movement of the movable objects, and 
 flowing fluid in the third, fourth, fifth and sixth conduits between the respective third and fourth chambers of the cylinders and in the seventh and eighth conduits between respective fifth six sixth chambers to equalize movement of the rams. 
 
     
     
       13. The system of  claim 12 , wherein moving the second three-position valve to a first position connects the fluid pressure source to the third fluid conduit and connects the fourth fluid conduit to the fluid reservoir for tilting the object clockwise, moving the second three-position valve to a third position connects the fluid pressure source to the fourth fluid conduit and connects the third fluid conduit to the fluid reservoir for tilting the object counterclockwise, moving the third three-position valve to a first position connects the fluid pressure source to the fifth fluid conduit and connects the sixth fluid conduit to the fluid reservoir for tilting the object clockwise, and moving the third three-position valve to a third position connects the fluid pressure source to the sixth fluid conduit and connects the fifth fluid conduit to the fluid reservoir for tilting the movable objects counterclockwise.